Certain physical objects may encounter different forms of vibrational loading in the course of their use. By way of example, a railroad car running board is used to define a narrow walkway along either a side or a roof of a railway car. Typically, running boards are made from steel and mounted to a railroad car via brackets at various attachment points using threaded fasteners or other suitable means.
As would be expected in the course of typical use, the running boards typically wear out, usually failing at one or more attachment points between the running board and the brackets and usually as a result of damage caused by vibrational loads that are transferred from the railroad car to the running board via the mounting brackets. These vibrational loads excite the fundamental natural frequencies of the running boards, thereby resulting in increased stress. It can be imagined that other physical objects having similar mounting schemes can be subject to similar wear and failure modes in the course of use/operation.